Nintendo on Friday said personal information of its customers in Japan may have been exposed following a massive unauthorized breach of its member website over last month.

The Japanese company said that the attackers gained access to nearly 24,000 accounts containing Club Nintendo members' real names, addresses, phone numbers and emails information.

The company said it has suspended the accounts and passwords used in the unauthorized access and is calling on members whose data may have been illegally accessed to change their passwords.

Club Nintendo has about 4 million users in Japan. It offers gamers points in exchange for registering their Nintendo products. The points can be saved up and exchanged for promotional goods, but Nintendo said it had detected no points that were used as a result of the illicit logins.